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1.
Cell ; 180(5): 895-914.e27, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-32142680

RESUMO

A safe and controlled manipulation of endocytosis in vivo may have disruptive therapeutic potential. Here, we demonstrate that the anti-emetic/anti-psychotic prochlorperazine can be repurposed to reversibly inhibit the in vivo endocytosis of membrane proteins targeted by therapeutic monoclonal antibodies, as directly demonstrated by our human tumor ex vivo assay. Temporary endocytosis inhibition results in enhanced target availability and improved efficiency of natural killer cell-mediated antibody-dependent cellular cytotoxicity (ADCC), a mediator of clinical responses induced by IgG1 antibodies, demonstrated here for cetuximab, trastuzumab, and avelumab. Extensive analysis of downstream signaling pathways ruled out on-target toxicities. By overcoming the heterogeneity of drug target availability that frequently characterizes poorly responsive or resistant tumors, clinical application of reversible endocytosis inhibition may considerably improve the clinical benefit of ADCC-mediating therapeutic antibodies.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/imunologia , Neoplasias/tratamento farmacológico , Proclorperazina/farmacologia , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados/farmacologia , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Apresentação de Antígeno/efeitos dos fármacos , Biópsia , Cetuximab/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Resistencia a Medicamentos Antineoplásicos/genética , Endocitose/efeitos dos fármacos , Endocitose/imunologia , Xenoenxertos , Humanos , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Células MCF-7 , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Camundongos , Neoplasias/genética , Neoplasias/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Trastuzumab/farmacologia
2.
Proc Natl Acad Sci U S A ; 119(27): e2122050119, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35763571

RESUMO

AIDS-defining cancers declined after combined antiretroviral therapy (cART) introduction, but lymphomas are still elevated in HIV type 1 (HIV-1)-infected patients. In particular, non-Hodgkin's lymphomas (NHLs) represent the majority of all AIDS-defining cancers and are the most frequent cause of death in these patients. We have recently demonstrated that amino acid (aa) insertions at the HIV-1 matrix protein p17 COOH-terminal region cause protein destabilization, leading to conformational changes. Misfolded p17 variants (vp17s) strongly impact clonogenic B cell growth properties that may contribute to B cell lymphomagenesis as suggested by the significantly higher frequency of detection of vp17s with COOH-terminal aa insertions in plasma of HIV-1-infected patients with NHL. Here, we expand our previous observations by assessing the prevalence of vp17s in large retrospective cohorts of patients with and without lymphoma. We confirm the significantly higher prevalence of vp17s in lymphoma patients than in HIV-1-infected individuals without lymphoma. Analysis of 3,990 sequences deposited between 1985 and 2017 allowed us to highlight a worldwide increasing prevalence of HIV-1 mutants expressing vp17s over time. Since genomic surveillance uncovered a cluster of HIV-1 expressing a B cell clonogenic vp17 dated from 2011 to 2019, we conclude that aa insertions can be fixed in HIV-1 and that mutant viruses displaying B cell clonogenic vp17s are actively spreading.


Assuntos
Linfócitos B , Antígenos HIV , HIV-1 , Linfoma Relacionado a AIDS , Produtos do Gene gag do Vírus da Imunodeficiência Humana , Linfócitos B/virologia , Variação Genética , Antígenos HIV/genética , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Linfoma Relacionado a AIDS/epidemiologia , Linfoma Relacionado a AIDS/virologia , Prevalência , Estudos Retrospectivos , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética
3.
Cytotherapy ; 26(2): 145-156, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38099895

RESUMO

BACKGROUND AIMS: Whole tumor cell lysates (TCLs) obtained from cancer cells previously killed by treatments able to promote immunogenic cell death (ICD) can be efficiently used as a source of tumor-associated antigens for the development of highly efficient dendritic cell (DC)-based vaccines. Herein, the potential role of the interferon (IFN)-inducible protein phospholipid scramblase 1 (PLSCR1) in influencing immunogenic features of dying cancer cells and in enhancing DC-based vaccine efficiency was investigated. METHODS: PLSCR1 expression was evaluated in different mantle-cell lymphoma (MCL) cell lines following ICD induction by 9-cis-retinoic acid (RA)/IFN-α combination, and commercial kinase inhibitor was used to identify the signaling pathway involved in its upregulation. A Mino cell line ectopically expressing PLSCR1 was generated to investigate the potential involvement of this protein in modulating ICD features. Whole TCLs obtained from Mino overexpressing PLSCR1 were used for DC loading, and loaded DCs were employed for generation of tumor antigen-specific cytotoxic T lymphocytes. RESULTS: The ICD inducer RA/IFN-α combination promoted PLSCR1 expression through STAT1 activation. PLSCR1 upregulation favored pro-apoptotic effects of RA/IFN-α treatment and enhanced the exposure of calreticulin on cell surface. Moreover, DCs loaded with TCLs obtained from Mino ectopically expressing PLSCR1 elicited in vitro greater T-cell-mediated antitumor responses compared with DCs loaded with TCLs derived from Mino infected with empty vector or the parental cell line. Conversely, PLSCR1 knock-down inhibited the stimulating activity of DCs loaded with RA/IFN-α-treated TCLs to elicit cyclin D1 peptide-specific cytotoxic T lymphocytes. CONCLUSIONS: Our results indicate that PLSCR1 improved ICD-associated calreticulin exposure induced by RA/IFN-α and was clearly involved in DC-based vaccine efficiency as well, suggesting a potential contribution in the control of pathways associated to DC activation, possibly including those involved in antigen uptake and concomitant antitumor immune response activation.


Assuntos
Antineoplásicos , Vacinas , Proteínas de Transferência de Fosfolipídeos/genética , Proteínas de Transferência de Fosfolipídeos/metabolismo , Calreticulina/metabolismo , Morte Celular Imunogênica , Antineoplásicos/metabolismo , Antígenos de Neoplasias , Imunidade , Células Dendríticas , Vacinas/metabolismo
4.
Cancer ; 128(10): 1937-1947, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35176174

RESUMO

BACKGROUND: Although the majority of human papillomavirus (HPV) infections are cleared by the immune system, a small percentage of them progress to develop HPV-driven cancers. Cervical cancer studies highlight that HPV persistence and cancer risk are associated with genetic factors, especially at the human leukocyte antigen (HLA) genes. This study was conducted to investigate such associations in head and neck cancer (HNC). METHODS: In all, 192 patients with HNC and 384 controls were genotyped with the Infinium Global Screening Array (Illumina, Inc). HLA variants were imputed with SNP2HLA, and an association analysis was performed by logistic regression. RESULTS: HPV-positive HNCs were significantly associated with single-nucleotide polymorphisms (SNPs) at DRB1_32660090 (P = 1.728 × 10-6 ) and DRB1_32660116 (P = 1.728 × 10-6 ) and with the amino acid variant DRB1_11_32660115 (P = 1.728 × 10-6 ). None of these associations were observed in the HPV-negative cohort, and this suggested their specificity to convey risk for HPV-associated HNCs. In general, associations observed for HPV-negative HNC were relatively weak, and variants in the HLA-DPA1 region were the strongest among them (P = 4.531 × 10-4 ). Several lead signals reported by previous HNC genome-wide association studies, including SNPs rs3135001 (P = .012), rs1049055 (P = .012), and rs34518860 (P = .029) and allele HLA-DQB1*06 (P = .009), were replicated in the current study. However, these associations were limited to the HPV-positive HNC group. Several cervical cancer-associated HLA variants, including SNPs rs9272143 (P = .002) and rs9271858 (P = .002) and alleles HLA-B-1501 (P = .009) and HLA-B-15 (P = .015), were also exclusively associated with HPV-positive HNC. CONCLUSIONS: HPV-positive HNC risk is associated with distinct HLA variants, and some of them are shared by both cervical cancer and HPV-positive HNC. Human papillomavirus (HPV)-positive head and neck cancer (HNC) risk is associated with distinct human leukocyte antigen variants, and some of them are shared by both cervical cancer and HPV-positive HNC. LAY SUMMARY: Cervical cancer studies highlight that human papillomavirus (HPV)-driven cancer risk is linked with human leukocyte antigen (HLA) polymorphism. Hence, the current study was designed to investigate the HLA associations in HPV-positive and HPV-negative head and neck cancer (HNC) and compare these associations with cervical cancer. Several lead signals reported by previous HNC and cervical genome-wide association studies were replicated in the current study. However, these associations were limited to the HPV-positive HNC group, and this suggests that HPV-positive HNC risk is associated with distinct HLA variants, and some of them are shared by both cervical cancer and HPV-positive HNC.


Assuntos
Alphapapillomavirus , Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Alphapapillomavirus/genética , Feminino , Estudo de Associação Genômica Ampla , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/genética , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe II/genética , Humanos , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Polimorfismo de Nucleotídeo Único
5.
Anal Bioanal Chem ; 414(29-30): 8401-8411, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36289103

RESUMO

Glycosylation is the most common post-translational modification of proteins, and glycosylation changes at cell surfaces are frequently associated with malignant epithelia including head and neck squamous cell carcinoma (HNSCC). In HNSCC, 5-year survival remains poor, averaging around 50% globally: this is partly related to late diagnosis. Specific protein glycosylation signatures on malignant keratinocytes have promise as diagnostic and prognostic biomarkers and as therapeutic targets. Nevertheless, HNSCC-specific glycome is to date largely unknown. Herein, we tested six established HNSCC cell lines to capture the qualitative and semi-quantitative N-glycome using porous graphitized carbon liquid chromatography coupled to electrospray ionisation tandem mass spectrometry. Oligomannose-type N-glycans were the predominant features in all HNSCC cell lines analysed (57.5-70%). The levels of sialylated N-glycans showed considerable cell line-dependent differences ranging from 24 to 35%. Importantly, α2-6 linked sialylated N-glycans were dominant across most HNSCC cell lines except in SCC-9 cells where similar levels of α2-6 and α2-3 sialylated N-glycans were observed. Furthermore, we found that HPV-positive cell lines contained higher levels of phosphorylated oligomannose N-glycans, which hint towards an upregulation of lysosomal pathways. Almost all fucose-type N-glycans carried core-fucose residues with just minor levels (< 4%) of Lewis-type fucosylation identified. We also observed paucimannose-type N-glycans (2-5.5%), though in low levels. Finally, we identified oligomannose N-glycans carrying core-fucose residues and confirmed their structure by tandem mass spectrometry. This first systematic mapping of the N-glycome revealed diverse and specific glycosylation features in HNSCC, paving the way for further studies aimed at assessing their possible diagnostic relevance.


Assuntos
Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Humanos , Fucose/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço , Polissacarídeos/metabolismo , Linhagem Celular , Glicômica
6.
Liver Int ; 41(1): 133-149, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32937024

RESUMO

BACKGROUND: Genetic variants of IFNL4 and PDCD1 genes have been shown to influence the spontaneous clearance of hepatitis C virus (HCV) infection. We investigated the IFNL4 rs12979860 and the PDCD1 polymorphisms in 734 HCV-positive patients, including 461 cases with liver disease of varying severity and 273 patients with lymphoproliferative disorders to determine the association of these genes with patient's outcome. METHODS: Expression levels of PDCD1 mRNA encoded by haplotypes were investigated by quantitative PCR in hepatocellular carcinoma (HCC) tissue and peripheral blood mononuclear cells. Flow cytometry was used to detect PD-1 and its ligand PD-L1. RESULTS: The frequency of IFNL4 rs12979860 C/T or T/T genotypes was significantly higher in patients with HCV-related diseases than blood donors (P < .0001). Patients expressing the IFNλ4 variant with one amino acid change that reduces IFNλ4 secretion was found increased in frequency in HCV-related diseases compared to HCC PDCD1 mRNA levels in HCC tissue were significantly higher in cases carrying the PD-1.3 A or the PD-1.7 G allele (P = .0025 and P = .0167). Linkage disequilibrium (LD) between PD-1.3 and IFNL4 was found in patients with mixed cryoglobulinaemia (MC) only (LD = 0 in HCC; LD = 72 in MC). PBMCs of MC patients expressed low levels of PD-L1 in CD19+IgM+B cells and of PD-1 in CD4+T cells suggesting the involvement of regulatory B cell-T cell interaction to the pathogenesis of MC. CONCLUSION: Collectively, our data indicate an important contribution of IFNλ4 expression to the development of HCV-related HCC and an epistatic contribution of IFNL4 and PDCD1 in MC. LAY SUMMARY: Studies of IFNL4 and PDCD1 genes are helpful to better understand the role of host genetic factors and immune antigens influencing the outcome of HCV-related diseases. Our data support an association between the expression of IFNλ4, which prevents the expression of IFNλ3, with all the different HCV-related diseases studied, and besides, evidence that a higher IFNλ4 expression is associated with hepatocellular at a younger age. The expression pattern of low PD-L1 on B cells and high PD-1 on CD4+T-cells in patients with HCV-positive cryoglobulinaemia suggests a critical role of the PD-1/PD-L1 signaling in modulating B cell-T cell interaction in this lymphoproliferative disease.


Assuntos
Carcinoma Hepatocelular , Hepatite C Crônica , Hepatite C , Neoplasias Hepáticas , Carcinoma Hepatocelular/genética , Hepacivirus , Hepatite C Crônica/complicações , Hepatite C Crônica/genética , Humanos , Interleucinas/genética , Leucócitos Mononucleares , Neoplasias Hepáticas/genética , Receptor de Morte Celular Programada 1/genética
7.
Br J Clin Pharmacol ; 86(9): 1711-1725, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32372470

RESUMO

The discovery of immune checkpoints and their role in modulating immune response have revolutionised cancer treatment in recent years. The immune checkpoints, cytotoxic T-lymphocyte-associated protein 4, programmed cell death protein 1 and its ligand, programmed cell death-ligand 1, have been extensively studied. Currently 7 monoclonal antibodies targeting these immune checkpoints are approved for treatment of various cancers. Inhibiting immune checkpoints has shown some success in clinic, however, a proportion of patients do not benefit from this treatment. Several other inhibitory molecules, in addition to lymphocyte-associated protein 4 and programmed cell death protein 1, are known to be involved in regulating immune response. To further improve patient outcomes, studies have examined targeting these inhibitory molecules through combination therapies. This review discusses the current landscape of combination therapies of checkpoint inhibitors.


Assuntos
Antineoplásicos Imunológicos , Neoplasias , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Terapia Combinada , Humanos , Imunoterapia , Neoplasias/tratamento farmacológico
8.
Hematol Oncol ; 37(2): 176-184, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30261551

RESUMO

Despite antiretroviral therapy, HIV+ individuals still have increased risk to develop lymphomas, including marginal zone lymphomas, suggesting that factors other than HIV-related immunosuppression are probably acting as lymphomagenic factors in the HIV setting. The possible pathogenic involvement of HIV p17 protein variants was investigated in a particularly informative case of HIV-related splenic marginal zone lymphoma, which was negative for oncogenic virus infections, thus allowing us to assess the possible direct contribution of these HIV-encoded proteins to lymphomagenesis. The presence of p17 protein was analyzed by immunohistochemistry in lymphoma tissue. Recombinant p17 protein derived from the dominant sequence detected in plasma and lymphoma biopsy was characterized for B-cell proliferation, clonogenicity in soft agar, in vitro tube formation and wound healing. Intracellular signaling was investigated by immunoblotting. HIV p17 protein was detected in reactive lymphoid follicles but not within lymphoma cells. An identical dominant variant p17 sequence, p17-Lyrm, carrying a 117 to 118 Ala-Ala insertion was detected in both plasma and lymphoma tissue. Recombinant p17-Lyrm enhanced B-cell proliferation and clonogenicity promoted the formation of capillary-like structures and enhanced endothelial cell migration. Unlike reference p17, the p17-Lyrm variant enhanced the activation of Akt and ERK, critical kinases in lymphomagenesis. p17-Lyrm clonogenic activity was dependent on the activation of Akt but not of ERK1/2. These results indicated that HIV p17 variants with distinct molecular signatures and functional properties may accumulate in lymphoid tissues of HIV-infected individuals where they may act as a local stimulus promoting the development of lymphomas.


Assuntos
Transformação Celular Viral , Antígenos HIV , Infecções por HIV , HIV-1 , Linfoma de Zona Marginal Tipo Células B , Mutagênese Insercional , Neoplasias Esplênicas , Produtos do Gene gag do Vírus da Imunodeficiência Humana , Feminino , Antígenos HIV/genética , Antígenos HIV/metabolismo , Infecções por HIV/genética , Infecções por HIV/metabolismo , Infecções por HIV/patologia , HIV-1/genética , HIV-1/metabolismo , Humanos , Linfoma de Zona Marginal Tipo Células B/genética , Linfoma de Zona Marginal Tipo Células B/metabolismo , Linfoma de Zona Marginal Tipo Células B/patologia , Linfoma de Zona Marginal Tipo Células B/virologia , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias Esplênicas/genética , Neoplasias Esplênicas/metabolismo , Neoplasias Esplênicas/patologia , Neoplasias Esplênicas/virologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Produtos do Gene gag do Vírus da Imunodeficiência Humana/metabolismo
9.
Int J Mol Sci ; 20(6)2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30875730

RESUMO

Brain metastases are the most prevalent of intracranial malignancies. They are associated with a very poor prognosis and near 100% mortality. This has been the case for decades, largely because we lack effective therapeutics to augment surgery and radiotherapy. Notwithstanding improvements in the precision and efficacy of these life-prolonging treatments, with no reliable options for adjunct systemic therapy, brain recurrences are virtually inevitable. The factors limiting intracranial efficacy of existing agents are both physiological and molecular in nature. For example, heterogeneous permeability, abnormal perfusion and high interstitial pressure oppose the conventional convective delivery of circulating drugs, thus new delivery strategies are needed to achieve uniform drug uptake at therapeutic concentrations. Brain metastases are also highly adapted to their microenvironment, with complex cross-talk between the tumor, the stroma and the neural compartments driving speciation and drug resistance. New strategies must account for resistance mechanisms that are frequently engaged in this milieu, such as HER3 and other receptor tyrosine kinases that become induced and activated in the brain microenvironment. Here, we discuss molecular and physiological factors that contribute to the recalcitrance of these tumors, and review emerging therapeutic strategies, including agents targeting the PI3K axis, immunotherapies, nanomedicines and MRI-guided focused ultrasound for externally controlling drug delivery.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/terapia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Antineoplásicos/farmacologia , Encéfalo/cirurgia , Neoplasias Encefálicas/imunologia , Quimiorradioterapia Adjuvante , Sistemas de Liberação de Medicamentos , Humanos , Imunoterapia , Terapia de Alvo Molecular , Nanomedicina , Nanopartículas , Resultado do Tratamento , Microambiente Tumoral
10.
Blood ; 127(11): 1403-9, 2016 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-26773045

RESUMO

Despite the immune reconstitution promoted by combined antiretroviral therapy (cART), lymphomas still represent the most common type of cancer in HIV-infected individuals. Cofactors related to immunodeficiency such as oncogenic viruses, chronic antigenic stimulation, and cytokine overproduction are thought to be the main drivers of HIV lymphomagenesis, although the current scenario does not convincingly explain the still-high incidence of lymphomas and the occurrence of peculiar lymphoma histotypes in HIV-infected patients under cART. Recent findings are challenging the current view of a mainly indirect role of HIV in lymphoma development and support the possibility that HIV may directly contribute to lymphomagenesis. In fact, mechanisms other than immune suppression involve biologic effects mediated by HIV products that are secreted and accumulate in lymphoid tissues, mainly within lymph node germinal centers. Notably, HIV-infected patients with lymphomas, but not those not affected by these tumors, were recently shown to carry HIV p17 protein variants with enhanced B-cell clonogenic activity. HIV p17 protein variants were characterized by the presence of distinct insertions at the C-terminal region of the protein responsible for a structural destabilization and the acquisition of novel biologic properties. These data are changing the current paradigm assuming that HIV is only indirectly related to lymphomagenesis. Furthermore, these recent findings are consistent with a role of HIV as a critical microenvironmental factor promoting lymphoma development and pave the way for further studies that may lead to the design of more effective strategies for an early identification and improved control of lymphomas in the HIV setting.


Assuntos
HIV/patogenicidade , Linfoma Relacionado a AIDS/etiologia , Animais , Linfócitos B/patologia , Linfócitos B/virologia , Transformação Celular Viral , Células Clonais , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genes gag , Centro Germinativo/virologia , HIV/genética , Antígenos HIV/genética , Antígenos HIV/fisiologia , Humanos , Hospedeiro Imunocomprometido , Ativação Linfocitária , Linfoma Relacionado a AIDS/classificação , Linfoma Relacionado a AIDS/patologia , Linfoma Relacionado a AIDS/virologia , Linfoma de Células B/etiologia , Linfoma de Células B/virologia , Camundongos , Camundongos Transgênicos , Microambiente Tumoral , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Produtos do Gene gag do Vírus da Imunodeficiência Humana/fisiologia
11.
Proc Natl Acad Sci U S A ; 112(46): 14331-6, 2015 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-26578780

RESUMO

Although in decline after successful anti-HIV therapy, B-cell lymphomas are still elevated in HIV-1-seropositive (HIV+) persons, and the mechanisms are obscure. The HIV-1 matrix protein p17 persists in germinal centers long after HIV-1 drug suppression, and some p17 variants (vp17s) activate Akt signaling and promote growth of transformed B cells. Here we show that vp17s derived from four of five non-Hodgkin lymphoma (NHL) tissues from HIV+ subjects display potent B-cell growth-promoting activity. They are characterized by amino acid insertions at position 117-118 (Ala-Ala) or 125-126 (Gly-Asn or Gly-Gln-Ala-Asn-Gln-Asn) among some other mutations throughout the sequence. Identical dominant vp17s are found in both tumor and plasma. Three of seven plasma samples from an independent set of NHL cases manifested multiple Ala insertions at position 117-118, and one with the Ala-Ala profile also promoted B-cell growth and activated Akt signaling. Ultradeep pyrosequencing showed that vp17s with C-terminal insertions are more frequently detected in plasma of HIV+ subjects with than without NHL. Insertion of Ala-Ala at position 117-118 into reference p17 (refp17) was sufficient to confer B-cell growth-promoting activity. In contrast, refp17 bearing the Gly-Asn insertion at position 125-126 did not, suggesting that mutations not restricted to the C terminus can also account for this activity. Biophysical analysis revealed that the Ala-Ala insertion mutant is destabilized compared with refp17, whereas the Gly-Asn form is stabilized. This finding provides an avenue for further exploration of structure function relationships and new treatment strategies in combating HIV-1-related NHL.


Assuntos
Transformação Celular Viral , Antígenos HIV/metabolismo , Infecções por HIV/metabolismo , HIV-1/metabolismo , Linfoma de Células B/metabolismo , Produtos do Gene gag do Vírus da Imunodeficiência Humana/metabolismo , Adulto , Linfócitos B/metabolismo , Linfócitos B/patologia , Linhagem Celular Tumoral , Feminino , Antígenos HIV/genética , Infecções por HIV/genética , Infecções por HIV/patologia , HIV-1/genética , Humanos , Linfoma de Células B/genética , Masculino , Pessoa de Meia-Idade , Mutagênese Insercional , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/genética , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética
12.
Int J Mol Sci ; 19(6)2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-29844297

RESUMO

Over the last decade, our understanding of the mechanisms underlying immune modulation has greatly improved, allowing for the development of multiple therapeutic approaches that are revolutionizing the treatment of cancer. Immunotherapy for gastric cancer (GC) is still in the early phases but is rapidly evolving. Recently, multi-platform molecular analyses of GC have proposed a new classification of this heterogeneous group of tumors, highlighting subset-specific features that may more reliably inform therapeutic choices, including the use of new immunotherapeutic drugs. The clinical benefit and improved survival observed in GC patients treated with immunotherapeutic strategies and their combination with conventional therapies highlighted the importance of the immune environment surrounding the tumor. A thorough investigation of the tumor microenvironment and the complex and dynamic interaction between immune cells and tumor cells is a fundamental requirement for the rational design of novel and more effective immunotherapeutic approaches. This review summarizes the pre-clinical and clinical results obtained so far with immunomodulatory and immunotherapeutic treatments for GC and discusses the novel combination strategies that are being investigated to improve the personalization and efficacy of GC immunotherapy.


Assuntos
Imunoterapia/métodos , Medicina de Precisão/métodos , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/terapia , Microambiente Tumoral/imunologia , Animais , Humanos , Neoplasias Gástricas/patologia
13.
Int J Mol Sci ; 19(6)2018 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-29882766

RESUMO

Gastric cancer (GC) is a common malignant neoplasm worldwide and one of the main cause of cancer-related deaths. Despite some advances in therapies, long-term survival of patients with advanced disease remains poor. Different types of classification have been used to stratify patients with GC for shaping prognosis and treatment planning. Based on new knowledge of molecular pathways associated with different aspect of GC, new pathogenetic classifications for GC have been and continue to be proposed. These novel classifications create a new paradigm in the definition of cancer biology and allow the identification of relevant GC genomic subsets by using different techniques such as genomic screenings, functional studies and molecular or epigenetic characterization. An improved prognostic classification for GC is essential for the development of a proper therapy for a proper patient population. The aim of this review is to discuss the state-of-the-art on combining histological and molecular classifications of GC to give an overview of the emerging therapeutic possibilities connected to the latest discoveries regarding GC.


Assuntos
MicroRNAs/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Animais , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/metabolismo , Instabilidade de Microssatélites , Mutação , Transdução de Sinais , Neoplasias Gástricas/classificação , Neoplasias Gástricas/metabolismo , Transcriptoma
14.
Int J Cancer ; 140(6): 1233-1245, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-27750386

RESUMO

The pathogenesis of classical Hodgkin lymphoma (cHL) is still enigmatic, largely because its tumor cells, the so-called Hodgkin and Reed-Stenberg (HRS) cells, invariably reside in a prominent reactive microenvironment, are rare and therefore difficult to analyze. On the other hand, the broadly investigated cHL-derived cell lines are not unequivocally considered as suitable and representative models for this puzzling disease. Based on current knowledge, it appears that the cross talk between the tumor cells and the reactive infiltrate of the microenvironment is complex and that multiple mechanisms occur, making cHL a very heterogeneous disease. In 20-40% of cHL cases, HRS cells carry a monoclonal infection by Epstein Barr virus (EBV), which is considered a tumor-initiating factor. In these cases, EBV shows a latency type II infection pattern with the expression of latent membrane protein-1 (LMP-1), a viral oncoprotein that mimics CD40 activation. This scenario is particularly intriguing for the pathogenesis of cHL arising in HIV-infected patients, which, for still obscure reasons, is invariably EBV-associated with LMP-1 expression in HRS cells. Recent evidences are consistent with the occurrence of different pathogenic pathways variably triggered by virus infections (EBV and HIV), genetic alterations, and interactions with critical microenvironmental components. This review focuses on the different microenvironmental niches that characterize cHL of the general population as well as cases of HIV-infected patients. A more comprehensive understanding of the complex interplay existing between HRS and tumor microenvironment is pivotal for the development of more effective treatments, particularly for relapsed or refractory diseases.


Assuntos
Infecções por Vírus Epstein-Barr/fisiopatologia , Doença de Hodgkin/virologia , Linfoma Relacionado a AIDS/virologia , Microambiente Tumoral , Proteínas da Matriz Viral/fisiologia , Antígenos CD/biossíntese , Antígenos CD/imunologia , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/virologia , Hibridização Genômica Comparativa , Citocinas/fisiologia , Receptor com Domínio Discoidina 1/fisiologia , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/virologia , Fibroblastos/fisiologia , Regulação Neoplásica da Expressão Gênica , Doença de Hodgkin/classificação , Doença de Hodgkin/etiologia , Doença de Hodgkin/imunologia , Doença de Hodgkin/patologia , Humanos , Imunocompetência , Ativação Linfocitária , Linfócitos do Interstício Tumoral/imunologia , Linfoma Relacionado a AIDS/etiologia , Linfoma Relacionado a AIDS/imunologia , Linfoma Relacionado a AIDS/patologia , Macrófagos/fisiologia , Modelos Biológicos , Proteínas de Neoplasias/fisiologia , Células de Reed-Sternberg/virologia , Transdução de Sinais , Latência Viral
15.
Hum Mol Genet ; 24(18): 5345-55, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26130695

RESUMO

Numerous genetic factors that influence breast cancer risk are known. However, approximately two-thirds of the overall familial risk remain unexplained. To determine whether some of the missing heritability is due to rare variants conferring high to moderate risk, we tested for an association between the c.5791C>T nonsense mutation (p.Arg1931*; rs144567652) in exon 22 of FANCM gene and breast cancer. An analysis of genotyping data from 8635 familial breast cancer cases and 6625 controls from different countries yielded an association between the c.5791C>T mutation and breast cancer risk [odds ratio (OR) = 3.93 (95% confidence interval (CI) = 1.28-12.11; P = 0.017)]. Moreover, we performed two meta-analyses of studies from countries with carriers in both cases and controls and of all available data. These analyses showed breast cancer associations with OR = 3.67 (95% CI = 1.04-12.87; P = 0.043) and OR = 3.33 (95% CI = 1.09-13.62; P = 0.032), respectively. Based on information theory-based prediction, we established that the mutation caused an out-of-frame deletion of exon 22, due to the creation of a binding site for the pre-mRNA processing protein hnRNP A1. Furthermore, genetic complementation analyses showed that the mutation influenced the DNA repair activity of the FANCM protein. In summary, we provide evidence for the first time showing that the common p.Arg1931* loss-of-function variant in FANCM is a risk factor for familial breast cancer.


Assuntos
Processamento Alternativo , Códon sem Sentido , DNA Helicases/genética , Reparo do DNA , Éxons , Adulto , Idade de Início , Alelos , Sítios de Ligação , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Estudos de Casos e Controles , DNA Helicases/metabolismo , Análise Mutacional de DNA , Feminino , Expressão Gênica , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Ribonucleoproteína Nuclear Heterogênea A1 , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Humanos , Metanálise como Assunto , Pessoa de Meia-Idade , Motivos de Nucleotídeos , Matrizes de Pontuação de Posição Específica , Ligação Proteica , Fatores de Risco , Adulto Jovem
16.
Breast Cancer Res Treat ; 161(1): 117-134, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27796716

RESUMO

PURPOSE: Cis-acting regulatory SNPs resulting in differential allelic expression (DAE) may, in part, explain the underlying phenotypic variation associated with many complex diseases. To investigate whether common variants associated with DAE were involved in breast cancer susceptibility among BRCA1 and BRCA2 mutation carriers, a list of 175 genes was developed based of their involvement in cancer-related pathways. METHODS: Using data from a genome-wide map of SNPs associated with allelic expression, we assessed the association of ~320 SNPs located in the vicinity of these genes with breast and ovarian cancer risks in 15,252 BRCA1 and 8211 BRCA2 mutation carriers ascertained from 54 studies participating in the Consortium of Investigators of Modifiers of BRCA1/2. RESULTS: We identified a region on 11q22.3 that is significantly associated with breast cancer risk in BRCA1 mutation carriers (most significant SNP rs228595 p = 7 × 10-6). This association was absent in BRCA2 carriers (p = 0.57). The 11q22.3 region notably encompasses genes such as ACAT1, NPAT, and ATM. Expression quantitative trait loci associations were observed in both normal breast and tumors across this region, namely for ACAT1, ATM, and other genes. In silico analysis revealed some overlap between top risk-associated SNPs and relevant biological features in mammary cell data, which suggests potential functional significance. CONCLUSION: We identified 11q22.3 as a new modifier locus in BRCA1 carriers. Replication in larger studies using estrogen receptor (ER)-negative or triple-negative (i.e., ER-, progesterone receptor-, and HER2-negative) cases could therefore be helpful to confirm the association of this locus with breast cancer risk.


Assuntos
Alelos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etiologia , Genes BRCA1 , Genes BRCA2 , Heterozigoto , Mutação , Biomarcadores Tumorais , Cromossomos Humanos Par 11 , Feminino , Expressão Gênica , Predisposição Genética para Doença , Variação Genética , Humanos , Locos de Características Quantitativas , Risco
17.
Artigo em Inglês | MEDLINE | ID: mdl-29026449

RESUMO

BACKGROUND: BRCA1 and BRCA2 mutations are associated with a higher risk of breast and ovarian tumors. This study evaluated the emotional states of women 1 month after having received the results of the genetic test and assessed eventual associations with the type of outcome, personal/familiar disease history and major socio-demographic variables. METHODS: The study, an observational retrospective one, involved 91 women, evaluated 1 month after receiving their results. Patients were administered the Hospital Anxiety and Depression Scale, the Profile of Mood States and emotional Thermometers. RESULTS: Anxiety was significantly higher than depression (p < 0.001), and 21.3% and 21.3% of the sample were, respectively, possible and probable cases for anxiety, whereas 13.5% and 10.1% were possible and probable cases for depression. Within the six mood states, Confusion-Bewilderment (M = 48.5) was the lowest, whereas Fatigue-Inertia (M = 52.3) was the highest. Differences were recorded within the ten assessed emotions too. Being a proband/nonproband and being or not a cancer patient were associated with many tested variables. CONCLUSION: The psycho-emotional screening of women undertaking genetic counseling is relevant and should cover a large range of dimensions.

18.
New Microbiol ; 40(1): 58-61, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28072889

RESUMO

HIV-1 p17 plays an important role in the virus life-cycle and disease pathogenesis. Recent studies indicated a high heterogeneity of p17. A high number of insertions in the p17 carboxy-terminal region have been more frequently detected in patients with non-Hodgkin lymphoma (NHL), suggesting a role of altered p17 in lymphomagenesis. Based on p17 heterogeneity, possible PBMC/plasma compartmentalization of p17 variants was explored by ultra-deep pyrosequencing in five NHL patients. The high variability of p17 with insertions at the carboxy-terminal region was confirmed in plasma and observed for the first time in proviral genomes. Quasispecies compartmentalization was evident in 4/5 patients. Further studies are needed to define the possible role of p17 quasispecies compartmentalization in lymphomagenesis.


Assuntos
Antígenos HIV/sangue , Antígenos HIV/metabolismo , Infecções por HIV/virologia , HIV-1 , Leucócitos Mononucleares/metabolismo , Produtos do Gene gag do Vírus da Imunodeficiência Humana/sangue , Produtos do Gene gag do Vírus da Imunodeficiência Humana/metabolismo , Regulação Viral da Expressão Gênica , Antígenos HIV/genética , Humanos , Filogenia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética
19.
Semin Cancer Biol ; 34: 58-69, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25953434

RESUMO

Epstein-Bar virus (EBV) is known to directly drive the neoplastic transformation of lymphoid cells resulting in the development of a variety of lymphoproliferative disorders. Emerging evidence however indicates that this final outcome is also related to the ability of EBV to shape microenvironment making it more conducive to cell transformation. Indeed, EBV up-regulates the production of several soluble factors promoting the growth and/or the survival of lymphoid cells and orchestrates a variety of complex mechanisms favoring their escape from anti-tumor immune responses. Furthermore, EBV-infected B lymphocytes actively secrete exosomes and recent investigation is now shedding light on the content and functional impact that these bioactive vesicles may have in bystander recipient cells. The complex interplay existing between EBV-carrying lymphoid cells and tumor microenvironment is now offering attractive targets of therapy that can be exploited to improve current therapeutic strategies for EBV-driven lymphoid malignancies.


Assuntos
Transformação Celular Viral , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/fisiologia , Linfoma/etiologia , Linfoma/patologia , Microambiente Tumoral , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/virologia , Biomarcadores , Efeito Espectador , Comunicação Celular , Infecções por Vírus Epstein-Barr/virologia , Exossomos/metabolismo , Humanos , Imunomodulação , Linfoma/metabolismo , Neovascularização Patológica/etiologia , Neovascularização Patológica/metabolismo , Transdução de Sinais , Células Estromais/metabolismo , Células Estromais/virologia
20.
Semin Cancer Biol ; 34: 52-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26118690

RESUMO

Patients with HIV infection are at increased risk of developing non-Hodgkin lymphoma and Hodgkin lymphoma. While the pathogenesis of these lymphomas is incompletely understood, evidence indicates that immune deregulation, genetic alterations and cytokine production play an important role in HIV lymphomagenesis. The lymphoma microenvironment in this heterogeneous group of lymphomas plays an equally critical role in their development, growth and progression. Important components of the microenvironment in HIV-related lymphomas include EBV and/or HHV-8 coinfection, reactive inflammatory cells, tumor microvasculature, and soluble factors. This paper provides a brief overview of HIV-related lymphomas and focuses on their lymphomagenesis and microenvironment.


Assuntos
Linfoma Relacionado a AIDS/etiologia , Linfoma Relacionado a AIDS/patologia , Microambiente Tumoral , Animais , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/virologia , Infecções por Herpesviridae/complicações , Infecções por Herpesviridae/virologia , Herpesvirus Humano 4/fisiologia , Herpesvirus Humano 8/fisiologia , Humanos , Linfoma Relacionado a AIDS/diagnóstico , Linfoma Relacionado a AIDS/metabolismo
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